Memory is a critical component of human cognition, and has major implications for everyday life and mental health. The long-term goals of this project are to increase our understanding of critical encoding and retrieval processes, and to help explain why memory is sometimes inaccurate, by using recently developed event-related functional magnetic resonance imaging techniques. The first 2 specific aims focus on basic aspects of encoding and retrieval, whereas the next 3 focus on memory distortion. The first specific aim is to characterize the functional anatomy of encoding, and test hypotheses concerning the involvement of specific brain regions in encoding variability, repetition priming, and response learning effects. Experiments 1-2 examine encoding manipulations that improve or impair subsequent memory, using techniques that link brain activity during encoding with later memory performance. The 2nd specific aim is to test hypotheses concerning the role of prefrontal cortex in specific aspects of strategic retrieval, which we do in Experiments 3 and 4 by manipulating the usefulness of recollective retrieval strategies. The 3rd specific aim is to characterize the neural underpinnings of true and false memory by testing the hypotheses that true memory, more than false memory, involves reactivation of sensory cortices involved in perceptual encoding, and that sensory reactivation reflects the influence of priming, a form of implicit memory. Experiments 5-10 accomplish this objective by comparing true and false memories, and conscious versus nonconscious recognition, for visual shapes, patterns, and objects. The 4th specific aim is to characterize encoding processes that result in memory errors in which people falsely recognize similar objects as the same ones they previously studied. Experiments 11-12 accomplish these objectives by using experimental procedures that relate particular encoding events to later true and false recognition. The 5th specific aim is to link work on memory distortion with research concerning perception of objects and scenes. Experiments 13 and 14 evaluate hypotheses regarding the role played by regions of parahippocampal cortex involved in contextual associations in false recognition of objects, and Experiment 15 examines the role of this region in boundary extension, where people "remember" aspects of a scene that were not presented in a photograph but are likely to have been present just beyond its borders. The proposed studies will increase our understanding of how memories are constructed, and will also contribute to efforts to improve memory.